Adverse response to pegylated interferon therapy in two patients with chronic hepatitis C

Pegylated interferons have recently been approved for treatment of hepatitis C. The safety of these formulations is reported to be similar to that of non-pegylated interferon. We present two patients who experienced exacerbations of their liver disease following administration of pegylated interferon alfa-2b. Vigilant monitoring of patients treated with these new agents is recommended.